We report novel supramolecular polyhedrons formed by three-dimensional self-assembly of multinuclear zinc(II)-12-membered tetraamine (=cyclen=1,4,7,10-tetraazacyclododecane) complexes with potentially multidentate ligands such as cyanuric acid (CA) and trithiocyanuric acid (TCA) in aqueous solution. Two new supermolecular frameworks were isolated by self-assembly of a tris (Zn
2+-cyclen) (Zn
3L
1) with di-(CA
2−) or tri-deprotonated cyanuric acid (CA
3−) in aqueous solution. One was a very stable 2:3 complex of Zn
3L
1 and CA
2− formed above pH6, which was stable in aqueous solution at neutral pH. The second was an unexpected supramolecular complex formed by 4:4 self-assembly of Zn
3L
1 and CA
3−, which was isolated by allowing a 1:1 mixture of Zn
3L
1 and CA to stand in aqueous solution at pH11.5. X-ray crystal analysis showed a highly symmetric 4:4 assembly complex with a cuboctahedral exterior and an inner hollow, which was schematically represented as a truncated tetrahedron formed by binding four equilateral triangles and four scalene hexagons with each other through CA
3−-Zn
2+ bonds. The 4:4 complex was found to be stable only in solid form or in DMSO solution and tends to revert to the 2:3 complex in the presence of H
2O. This problem has been overcome by replacing CA with TCA, of which the thioimide functions possess lower p
Ka values than those of CA. TCA acted as a tridentate donor for three Zn
3L
1 at neutral pH to yield a similar type of 4:4 self-assembling supercomplex, in which the deprotonated TCA
3− in an aromatic 1,3,5-triazine binds to Zn
3L
1 through Zn
2+-S
- (exocyclic) coordination bonds, and thus the 4:4 assembly is a chiral twisted cuboctahedron. More interestingly, this supramolecular capsule was found to be stabilized by encapsulation of various size-matched and hydrophobic guest molecules such as adamantane in the twisted truncated cavity. Finally, we succeeded in synthesizing new supramolecular trigonal prisms from linear multinuclear zinc complexes such as
p-Zn
2L
2 and
p,
p-Zn
3L
3 with TCA
3− in aqueous solution at neutral pH, which are stabilized by Zn
2+-S
- or Zn
2+-N
- coordination bonds and hydrogen bonds in aqueous solution at neutral pH. Thus we discovered a new approach to the design of various supramolecular structures in aqueous solution.
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